The Etruscan shrew (Suncus etruscus), also known as the Etruscan pygmy shrew or the white-toothed pygmy shrew is the smallest known mammal by mass, weighing only about 1.8 grams (0.063 oz) on average (The bumblebee bat is regarded as the smallest mammal by skull size).The Etruscan shrew has a body length of about 4 centimetres (1.6 in) excluding the tail. It is characterized by very rapid movements and a fast metabolism, eating about 1.5–2 times its own body weight per day.